• Atlases of the Brain
• Atlas of Human Anatomy in Cross Section
• Anatomy Tutorials
• Digital Anatomist
• Electric Lung Anatomy
• The Human Brain: Dissections of the Real Brain
• Illustrated Encyclopedia of Human Anatomic Variation
• LUMEN Visible Human Anatomy
• Pelvis and Perineum
• Whole Brain Atlas

Anesthesia

• Virtual Anesthesia Textbook

Biochemistry

• Indiana State University
• Medical Biochemistry - from the University of Kansas Medical Center
• MIT Biology Hypertextbook
• NetBiochem

Bioethics

• Bioethics Internet Project
• Ethics Updates
• Kennedy Institute of Ethics, Georgetown University
• University of Toronto Joint Center for Bioethics

Dermatology

• Dermatology Image Bank
• Dermatology Online Atlas
• eMedicine
• Flight Surgeon's Manual
• Introduction to Basic Dermatology
• Iowa Family Practice Handbook
• The Merck Manual of Diagnosis and Therapy

Embryology

• Visible Embryo
• Medical Embryology
• Multi-Dimensional Human Embryo

Emergency Medicine

• eMedicine
• First Aid Anatomy
• First Aid for Soldiers
• Iowa Family Practice Handbook
• The Merck Manual of Diagnosis and Therapy
• U.S. Navy Standard First Aid Course

Evidence Based Medicine

• Cochrane Collaboration
• DARE
• Evidence Based Medicine Resources from IntensiveCare.com
• Evidence Based Medicine Resources from U.S. Navy

Family Medicine

• AHCPR Clinical Practice Guidelines
• eMedicine Medicine and Surgery
• Flight Surgeon's Manual
• General Medical Officer Manual
• Iowa Family Practice Handbook
• National Guideline Clearinghouse
• Primary Care Clinical Practice Guidelines Index
• Virtual Naval Hospital

• Complete Home Medical Guide

Histology

• JayDoc HistoWeb
• LUMEN Histology
• U of Wisconsin Histology Atlas

History of Medicine

• Images from the History of Medicine

Informatics

• Guide to Medical Informatics, the Internet, and Telemedicine
• Handbook of Medical Informatics

Internal Medicine

• AHCPR Clinical Practice Guidelines
• Asthma Treatment Handbook
• Centers for Disease Control Guidelines for Treating Sexually Transmitted Diseases
• ECGs by Example
• eMedicine Medicine and Surgery
• FDA Handbook of Foodborne Pathogenic Microorganisms and natural Toxins
• Flight Surgeon's Manual
• General Medical Officer Manual
• Guide to Malaria Prevention and Control
• Iowa Family Practice Handbook
• Lung Tumors
• Medical Management of Biological Casualties: Handbook
  (third edition, 1998)-by United States Army Medical Research Institute of Infectious Diseases
• National Cancer Institute PDQ Clinical Cancer Information
• National Guideline Clearinghouse
• Oncolink
• Primary Care Clinical Practice Guidelines Index
• The Longitudinal Muscle in Esophageal Disease
• The Merck Manual of Diagnosis and Therapy
• Yale University School of Medicine Heart Book, ed. by Barry L. Zaret, Marvin
  Moser, and Lawrence S. Cohen (PDF files at Yale)
• Virtual Naval Hospital

Medical Law

• The House Officer's Survival Guide: Rules, Laws, Lists and Other Medical Musings
  by Lawrence Martin (HTML at mtsinai.org)
• Laws and Regulations of the American Medical Association

Microbiology

• Atlas of Medical Parasitology
• MedMicro Profiles: Bacteriology Identification Scheme

Neurology

• eMedicine Neurology
• Flight Surgeon's Manual
• Iowa Family Practice Handbook
• The Merck Manual of Diagnosis and Therapy

Neurosurgery

• UNC's Neurosurgery Resident's Online Handbook

Obstetrics and Gynecology

• Human Reproduction
• Iowa Family Practice Handbook - Obstetrics
• Iowa Family Practice Handbook - Gynecology
• Operational Obstetrics and Gynecology
• Surgical Emergencies in Obstetrics and Gynecology
• The Merck Manual of Diagnosis and Therapy

Ophthalmology

• Digital Atlas of Ophthalmology
• eMedicine Ophthalmology
• Flight Surgeon's Manual
• Iowa Family Practice Handbook
• The Merck Manual of Diagnosis and Therapy

Orthopaedic Surgery

• Electronic Orthopaedic Textbook
• Iowa Family Practice Handbook
• The Merck Manual of Diagnosis and Therapy
• Wheeless' Textbook of Orthopaedics

Otolaryngology

• eMedicine Otolaryngology
• Flight Surgeon's Manual
• Iowa Family Practice Handbook

Pathology

• AIDSPATH Electronic Text Book of AIDS Pathology University of Utah
• Cornell Path Notes
• Digital Slice of Life
• Gram Staining
• Laboratory Test Interpretation
• Pathology Laboratories Handbook University of Michigan
• WebPath

Pediatrics

• Clinical Genetics
• eMedicine - Pediatrics
• GeneralPediatrics.com
• Iowa Family Practice Handbook
• Online Mendelian Inheritance in Man
• PaediapaediaTM An Imaging Encyclopedia of Pediatric Disease
• Pediatric Surgery Handbook
• The Merck Manual of Diagnosis and Therapy

Pharmacology

• Internet Self Assessment in Pharmacology
• Iowa Family Practice Handbook
• RxList
• The Merck Manual of Diagnosis and Therapy
• USP Pharmacopeia

Physical Examination

• LUMEN Screening Physical Exam

Physical Medicine and Rehabilitation

• Rehabilitation - The Merck Manual

Preventive Medicine

• CDC Prevention Guidelines Database
• Clinician's Handbook of Preventive Services
• Guide to Clinical Preventive Services, Second Edition
• Manual of Naval Preventive Medicine

Psychiatry

• Emergency Psychiatry Service Handbook
• Flight Surgeon's Manual
• Iowa Family Practice Handbook
• Internet Mental Health
• The Merck Manual of Diagnosis and Therapy

Radiology and Radiation Oncology

• Approaches To Differential Diagnosis In Musculoskeletal Imaging
• Introduction to Basic Radiology
• Normal Radiologic Anatomy
• The Basic of MRI Multimedia Textbook
• USUHS Chest X-Ray Review
• USUHS Radiologic Anatomy Browser

Surgery

• eMedicine Medicine and Surgery
• eMedicine Plastic Surgery
• Emergency War Surgery Handbook
• Ethicon Wound Closure Manual
• Ethicon Knot Tying Manual Iowa
  Family Practice Handbook

Travel Medicine

• Centers for Disease Control Travel Medicine
• Emporiatrics: Travel Medicine

Urology

• Iowa Family Practice Handbook
• The Merck Manual of Diagnosis and Therapy

Miscellaneous

• Diagnostic Procedures Handbook
• Drug Slang Dictionary: from Indiana Prevention Resource Center
• GeneClinics is a medical knowledge base relating genetic testing to the diagnosis, management, and genetic
  counseling of individuals and families with specific inherited disorders
• Laboratory Tests Handbook University of Texas / Houston
• Medical Informatics TextBook at Columbia
• Multimedia Textbooks: from University of Iowa Virtual Library